This invention relates to a hydraulic servomechanism for controlling the position of a sliding element such as a movable pulley element or conical disc of a pulley in an infinitely variable automatic transmission or the like.
Various types of hydraulic servomechanisms are conventionally known. Most of these conventional servomechanism are adapted to control the position of a sliding element to be controlled, by varying the flow rate of hydraulic fluid supplied to a hydraulic pressure chamber for urging the sliding element. This control manner, however, requires a valve mechanism and a valve control system, rendering the servomechanism complicated in structure, resulting in high manufacturing costs.